Storage-driven changes in raspberry quality: insights from volatile organic compounds, sensory and physical analyses

The shelf-life of fresh raspberries after harvesting is short (2-5 days in ambient temperature), due to their high respiration rate and morphological fragility, reducing their commercialization potentiality. This study, within the SISTERS project funded by the European Union’s Horizon 2020 (GRANT AGREEMENT Nº101037796), investigates the chemical evolution of three raspberry varieties (Dafne, Lagorai, Experimental) under three distinct storage conditions for 15 days: SB (StoreBox: a smart container), STD (standard PET clamshell), and SIS (SISTERS biodegradable clamshell). The goal was to assess how storage conditions influence the volatile composition of raspberries during shelf-life, with a particular focus on key aroma-related compounds. Volatile organic compound profiles were acquired both by SPME/GC-MS and by PTR-ToF-MS. An initial exploration of the VOCs data was conducted using Principal Component Analysis (PCA). The PCA biplots revealed distinct clustering patterns based on storage conditions, indicating that different preservation methods significantly influence chemical profiles over time. The loading analysis identified the most influential chemical compounds driving differentiation between storage conditions. Among them, limonene, 2-nonanone, acetic acid, (E)-2-hexenal, and nonanal played key roles in distinguishing SB, STD, and SIS conditions. Similar profiles were obtained by rapid measurements by PTR-ToF-MS. The time evolution analysis showed that standard packaging resulted in greater variability in volatile compounds, likely due to accelerated oxidation and degradation, while SIS packaging and SB container contributed to more stable profiles over time. Overall, our results demonstrate that the uses of SB container and of SIS packaging better preserve volatile profiles in raspberries, while STD packaging leads to faster chemical changes. These findings provide valuable insights for optimizing post-harvest storage techniques to maintain aroma and quality. Further data analyses are underway to evaluate other aspects of product quality (e.g., colour changes, texture and microbiological analysis) and to provide a more comprehensive picture of raspberry quality evolution during storage.